error during REPL precompilation on CI while trying to exercise the shell mode

[nsajko]

  2 dependencies had output during precompilation:
┌ REPL
│  ERROR: IOError: could not spawn `/shells/bash -c '(pwd) && true'`: no such file or directory (ENOENT)
└
┌ REPL
│  ERROR: IOError: could not spawn `/shells/bash -c '(pwd) && true'`: no such file or directory (ENOENT)
└

• https://buildkite.com/julialang/julia-master/builds/45592#01957707-28f7-4b7c-a60f-fa1570a95a60/836-2792

Perhaps the SHELL environment variable (or JULIA_SHELL) has the wrong value in CI? Or perhaps shelling out is intentionally disabled during CI, in which case perhaps this line should be deleted from the REPL precompilation workload:

julia/stdlib/REPL/src/precompile.jl

Line 63 in 7d84c53

; pwd

[KristofferC]

which case perhaps this line should be deleted from the REPL precompilation workload:

It serves to precompile the shell repl mode so it would be better to replace it with some other command that is more likely to be executable.